1. Technical Field
An aspect of the disclosure relates to an image reader and a sheet conveyer.
2. Related Art
An image reader including an upper chassis and a lower chassis, which face each other across a conveyer path to convey a sheet, is known. In order to detect multiple feed of sheets conveyed along the conveyer path, for example, the image reader may be equipped with a sensor including an emitter and a receiver. The emitter may be disposed, for example, on the lower chassis, and the receiver may be disposed on the upper chassis. The emitter may emit ultrasonic waves toward the conveyer path, and the receiver may receive the emitted ultrasonic waves. Thus, the sensor may output detected signals, by which multiple feed of sheets conveyed along the conveyer path can be recognized.
The receiver to receive the ultrasonic waves may have such a characteristic that sensitivity thereof may be lowered when temperature in the receiver is low. Therefore, in the image reader, the receiver may be disposed in a position adjacent to a light source of a display unit, which is disposed on the upper chassis. Thus, the receiver may be maintained warmed by heat from the light source.